Demographic and clinical characteristics
| Variable | No. (%) of participants* | p value† | Low-risk youth v. high-risk youth | ||
|---|---|---|---|---|---|
| Healthy controls n = 49 | Low-risk youth n = 50 | High-risk youth n = 50 | p value‡ | ||
| Age, yr, mean ± SD | 14.60 ± 2.43 | 14.06 ± 2.53 | 13.77 ± 2.58 | 0.251 | 0.569 |
| Sex, male | 30 (61.2) | 33 (66.0) | 33 (66.0) | 0.849 | 1.000 |
| Handedness, right | 47 (96.0) | 40 (80.0) | 43 (86.0) | 0.057 | 1.000 |
| BMI, mean ± SD | 22.53 ± 4.61 | 23.80 ± 6.76 | 24.21 ± 7.38 | 0.402 | 0.776 |
| Z score | 0.56 ± 1.06 | 0.76 ± 1.19 | 0.83 ± 1.31 | 0.532 | 0.801 |
| Percentile | 65.49 ± 29.04 | 68.34 ± 29.42 | 70.60 ± 32.57 | 0.702 | 0.716 |
| ADHD type | |||||
| ADHD-I | – | 28 (56.0) | 13 (26.0) | – | < 0.001 |
| ADHD-H | – | 0 (0.0) | 1 (2.0) | – | – |
| ADHD-C | – | 22 (44.0) | 36 (72.0) | – | < 0.001 |
| Previous psychostimulant exposure | – | 17 (34.0) | 23 (46.0) | – | 0.221 |
| ADHD-R, mean ± SD | |||||
| Total score | 3.20 ± 3.93 | 33.46 ± 10.00 | 36.00 ± 10.60 | < 0.001 | 0.221 |
| Inattention subscale | 1.86 ± 2.27 | 20.96 ± 4.83 | 19.98 ± 5.66 | < 0.001 | 0.354 |
| Hyperactivity/impulsivity subscale | 1.35 ± 2.10 | 12.50 ± 8.06 | 16.02 ± 7.21 | < 0.001 | 0.023 |
| CDRS-R total score, mean ± SD | 18.00 ± 2.31 | 24.04 ± 5.91 | 27.30 ± 8.18 | < 0.001 | 0.024 |
| YMRS total score, mean ± SD | 0.73 ± 1.93 | 2.98 ± 3.29 | 5.76 ± 5.67 | < 0.001 | 0.004 |
| CGAS total score, mean ± SD | 88.27 ± 5.88 | 52.60 ± 6.86 | 50.56 ± 7.26 | < 0.001 | 0.152 |
| CGI-S, mean ± SD | – | 4.02 ± 0.55 | 4.30 ± 0.68 | - | 0.026 |
| CBCL, mean ± SD | |||||
| Total score | 6.81 ± 6.55 | 37.38 ± 18.18 | 54.17 ± 28.64 | < 0.001 | < 0.001 |
| Internalizing subscore | 2.30 ± 2.40 | 8.19 ± 6.37 | 12.74 ± 9.12 | < 0.001 | 0.001 |
| Externalizing subscore | 1.49 ± 1.78 | 8.29 ± 6.83 | 14.85 ± 12.39 | < 0.001 | < 0.001 |
| Dysregulation score | 2.87 ± 2.85 | 21.10 ± 9.65 | 26.34 ± 13.34 | < 0.001 | 0.009 |
ADHD = attention-deficit/hyperactivity disorder; ADHD-R = Attention-Deficit Hyperactivity Disorder Rating Scale; BMI = body mass index; CBCL = Child Behaviour Checklist; CDRS-R = Children’s Depression Rating Scale-Revised; CGAS = Children’s Global Assessment Scale; CGI-S = Clinical Global Impression-Severity Scale; SD = standard deviation; YMRS = Young Mania Rating Scale.
↵* Unless indicated otherwise.
↵† One-way analysis of variance or χ2.
↵‡ t test or χ2.